The information processing technology between semiconductor chips or boards using an optical communication technology is getting spotlights because it can solve the problems contained in copper interconnect such as the electromagnetic interference (EMI), impedance mismatch, and signal distortion (skew). Therefore, an opto-electric interconnect module using an optical interconnect and an electric interconnect as interconnect of a printed circuit board is suggested. However, the manufacturing cost of a dielectric optical waveguide used for the opto-electric interconnect module is very expensive.
Recently, a metal line optical waveguide in which a metal line is inserted in the dielectric material is getting spotlight as a technology that replaces the dielectric optical waveguide. However, the waveguide loss of the metal line waveguide is much higher than the waveguide loss of the dielectric optical waveguide. A very thin metal line is required and it is difficult to simultaneously transmit high power line or electric signal together with the optical signal due to the high resistance of the metal line.